Overestimation of the field-effect mobility via transconductance measurements and the origin of the output/transfer characteristic discrepancy in organic field-effect transistors

In this work, we characterized poly(quinacridone-diphenylquinoxaline) (PQCTQx). PQCTQx was synthesized by a Suzuki coupling reaction and the synthesized PQCTQx was used as a polymeric semiconducting material in organic field-effect transistors (OFETs) to research the potential of using quinacridone derivatives. The measured field-effect mobility of the pristine PQCTQx film was 6.1 × 10−3 cm2/(V·s). A PQCTQx film heat-treated at 150 °C exhibited good field-effect performances with a hole mobility of 1.2 × 10−2 cm2/(V·s). The improved OFET behaviors resulting from the mild thermal treatment was attributed to improved packing of the molecules in the film, as determined using X-ray diffraction, and to decreased channel resistance.

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Degradation of organic field-effect transistors made of pentacene

Journal of Materials Research ◽

10.1557/jmr.2004.0267 ◽

2004 ◽

Vol 19 (7) ◽

pp. 1999-2002 ◽

Cited By ~ 60

Author(s):

Ch. Pannemann ◽

T. Diekmann ◽

U. Hilleringmann

Keyword(s):

Charge Carrier ◽

Threshold Voltage ◽

Field Effect ◽

Gate Dielectric ◽

Field Effect Transistors ◽

Ambient Air ◽

Organic Field Effect Transistors ◽

Organic Thin Film ◽

Field Effect Mobility ◽

Semiconducting Material

This article reports degradation experiments on organic thin film transistors using the small organic molecule pentacene as the semiconducting material. Starting with degradation inert p-type silicon wafers as the substrate and SiO2 as the gate dielectric, we show the influence of temperature and exposure to ambient air on the charge carrier field-effect mobility, on-off-ratio, and threshold-voltage. The devices were found to have unambiguously degraded over 3 orders of magnitude in maximum on-current and charge carrier field-effect mobility, but they still operated after a period of 9 months in ambient air conditions. A thermal treatment was carried out in vacuum conditions and revealed a degradation of the charge carrier field-effect mobility, maximum on-current, and threshold voltage.

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Gradient Copolymerization towards High-performance Monocomponent Polymers for Energy and Charge Storages

10.21203/rs.3.rs-847201/v1 ◽

2021 ◽

Author(s):

Yuanwei Zhu ◽

Wanlong Lu ◽

Nan Qiao ◽

Huize Cui ◽

Zhipeng Hu ◽

...

Keyword(s):

Energy Density ◽

Field Effect ◽

High Performance ◽

Field Effect Transistors ◽

Filtration Efficiency ◽

Nano Composites ◽

Organic Field Effect Transistors ◽

Field Effect Mobility ◽

Nano Composite ◽

Practical Applications

Abstract Polymers with excellent dielectric and electret capabilities are crucial for energy storage films, organic electronics and environmental filtrations. Nanocomposites is an emerging effective method, but the characteristics of complicated preparation, poor uniformity and high cost restrict its massive and practical applications. Here, we propose a gradient copolymerization strategy with controllable micro-phase interfaces for dielectric capability modulation, and gradient ethylene-styrene copolymer (PESt) exhibits extraordinarily enhanced dielectric, electrical insulating and electret properties against polyethylene and polystyrene. PESt exhibits a dielectric energy density towards 23 J·cm− 3, far exceeding commercially applied polymers and is comparable to nano-composites. By applying PESt as electret layer in organic field-effect transistors, largely enhanced memory window, optimized stability and field-effect mobility over 27 cm2·V− 1·s− 1 are achieved. Finally, PESt electret is employed in environmental filtrations with 20% enhancement in filtration efficiency. The simplicity and processability of gradient copolymerization against nano-composite, further suggest its potential in designing high-performance dielectric/electret polymers.

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Morphology and Field-Effect Mobility Characterization of Planar Five-Ring-Fused Dithiophene-Dione

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.331.452 ◽

2013 ◽

Vol 331 ◽

pp. 452-455 ◽

Cited By ~ 1

Author(s):

Jing Wang

Keyword(s):

Field Effect ◽

Field Effect Transistors ◽

Layer By Layer ◽

Organic Field Effect Transistors ◽

Field Effect Mobility ◽

X Ray Diffraction ◽

Vapor Growth ◽

Face To Face ◽

Atomic Force ◽

Substrate Temperatures

The thin films of compound 2,7-dihexyl-4,9-dihydro-s-indaceno [1,2-b:5,6-b']- dithiophene-4,9-dione were grown by physical vapor growth at different substrate temperatures. The morphology of surfaces was characterized by atomic force microscope and X-ray diffraction, which exhibits increased crystal grain size and film order with the increase of substrate temperature. The molecule exhibits layer-by-layer packing on the Si/SiO2 substrate and the tilt angle with respect to the substrate is 49.5°, which form extended slipped face-to-face π-stacking in each layer. This result indicates that molecular packing in the thin film is similar to that in the single crystal. The organic field-effect transistors (OFETs) incorporating this compound shows a field effect mobility at the order of 10-3 cm2V-1s-1 and an on-off ratio of 4 × 106 with good air-stability.

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Influence of the Contact Thickness on Electrical Performance of Staggered and Planer p-Channel Organic Field Effect Transistors

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.622-623.1434 ◽

2012 ◽

Vol 622-623 ◽

pp. 1434-1438 ◽

Cited By ~ 1

Author(s):

Brijesh Kumar ◽

B.K. Kaushik ◽

Y.S. Negi

Keyword(s):

Threshold Voltage ◽

Field Effect ◽

Field Effect Transistors ◽

Electrical Performance ◽

Thickness Variation ◽

Organic Field Effect Transistors ◽

Field Effect Mobility ◽

Effect Transistor ◽

Current Value ◽

Good Agreement

The influence of contact thickness on electrical performance of bottom gate Organic Field Effect Transistor (BG-OFET) with staggered and planer structures is studied in this paper. Two dimensional device simulation is performed with identical dimensions for both devices which show a good agreement between simulated and measured results. Contact thickness is varied from 0nm to 20nm for planer and staggered structures. The electrical characteristics are strongly affected by the contact thickness variation. With increasing contact thickness, the threshold voltage shifts from negative to positive. The simulation results indicate that saturation current value of staggered structure is higher than that of planer. Although the current does not increase in staggered structure due to its increasing contact thickness, while the current in planer structure increases up to three times. However, current in planer is still below the current in staggered structure. The extracted field effect mobility and current on-off ratio at 20nm electrode thickness for staggered structure is 0.67 cm2/V.s and 108, respectively. It has been observed that the field effect mobility, threshold voltage, sub-threshold slope, transconductance and current on-off ratio can be modified by varying contact thickness. Analysis of the results clearly demonstrates the significance of controlling the contact thickness in planer and staggered OFETs. It even offers a way to control OFETs parameters.

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